Safety device for fire-extinguishing apparatus



Jan. 22, 1957 R. E. DOWNHAM ET AL 2,778,435

SAFETY DEVICE FOR FIRE-EXTINGUISHING APPARATUS 2 Sheets-Sheet l Filed Oct,

INVENTORS. ROY E. DOWNHAM F/G. By ALDEN w. ALLEN Jan. 22, 1957 R. E. DOWNHAM ETAL 2,778,435

SAFETY DEVICE FOR FIRE-EXTINGUISHING APPARATUS INVENTORS ROY E. DOWNHAM By ALDEN w.- ALLEN United States Patent SAFETY DEVECE FQR FKREEXTINGUISHING APPARATUS Roy E. Downham, Marinette, Wis., and Alden W. Allen,

Minneapolis, Minn, assignors to Ansul Chemical Company, Marinette, Wis., a corporation of Wisconsin Application October 25, W55, Serial No. 542,573

Claims. (Cl. 169-31) The subject-matter of this patent may be used by or for the Government for governmental purposes, without the payment of any royalties to us.

This invention relates to a fire-extinguishing apparatus for holding and dispensing a pressurized fire-extinguishing agent. More specifically, the invention relates to an improvement on the type extinguisher wherein the pressurized agent is contained in a sealed container and in which a means is provided for rupturing the seal and to provide control of the flow of fire-extinguishing agent after the seal has been ruptured.

Details and advantages of the invention will be apparent from the accompanying drawings and the following description, wherein:

Figure l is a vertical sectional view Of the fire-fighting apparatus before the ring pin has been removed,

Figure 2 is a sectional view of the head end of the fire extinguisher after the ring pin has been removed, and

Figure 3 is a sectional view of the head end of the fire extinguisher with the trigger depressed in the operate or discharge position.

Referring to the drawings, the fire extinguisher comprises a cylindrical container 2 for storing a pressurized fire-extinguishing agent 3. The container 2 is provided with a pick-up tube 4 which extends to the bottom and is retained in the neck portion 2a of said container. The neck 2a of the container 2 is sealed with a frangible disc 6. The frangible disc in this structure functions both as a gas tight seal which may be ruptured by the puncture pin it as shown in Figure 3, and as a bursting disc to relieve the pressure in the container in the event the extinguisher is over charged or subjected to excessive heat.

The head is internally bored to receive an axially movable puncture pin 1% surrounded by a plurality of spaced sealing washers ll which are compressed by spring 18 intermediate the washers which are retained in the bore. The puncture pin it? is provided with a cutting edge 5 at its lower end which is adapted to pierce the frangible seal 6 when the puncture pin is depressed. The puncture pin is also provided with a sealing plug 13 which is in seating engagement with sealing ring 14 when the puncture pin is in the raised position. The position of the puncture pin is determined by the position of the actuation lever 7 which rotates about pin 3 and is pivotally connected to the puncture pin at point 9.

A spring 12 is provided which urges the actuation lever so that the puncture pin is raised away from the sealing disc and toward the position shown in Figure 2 where the sealing plug 13 is in engagement with sealing ring 14. The head 15 is drilled at 16 and the actuating lever 7 is drilled at 17, as shown in Figure 2, so that when the ring pin 19 is placed through these aligned holes, as shown in Figure l, the puncture pin it) is prevented from puncturing the frangible seal 6 and the sealing plug 13 is held from seating engagement with sealing ring 14.

When it is desired to use the extinguisher, the ring pin 19 is manually removed. The spring 12 will then urge 2,778,435 Patented Jan. 22, 1957 the puncture pin to its upper position, as shown in Figure 2. Upon actuating lever 7, puncture pin will be depressed so as to puncture disc 6, as shown in Figure 3. The fire-extinguishing agent 3 will thereupon flow out through passageway 20 and nozzle 21 provided in the head 15, as shown by the arrow in Figure 3, as long as lever '7 is retained against the pressure of spring 12. Upon release of lever 7, puncture pin will be automatically moved upwardly to the position, as shown in Figure 2, whereupon plug 13 will seal passageway20 and prevent further flow of the fire-extinguishing agent '3.

In the construction as described, it will be evident that the frangible seal may function as a safety seal and relieve the pressure in the extinguisher in the event the extinguisher is over-pressurized or subjected to excessive heat as long as the ring pin is in position. In previous constructions, no means was provided for the pressure to escape from between the sealing plug and the sealing seat and dangerously high pressures could be encountered in the extinguisher in event of over-pressurization or excessive heat unless a separate safety device is provided in the shell or in the head of the extinguisher.

Operating means and safety devices other than those described may be used in the present invention and it is intended that changes and modifications may be made in the specific construction previously described which are intended to be included in the appended claims.

We claim:

1. A fire-extinguishing apparatus comprising a pressure container for the fire-extinguishing agent, a frangible seal closing the mouth of said container, a housing having a passage therethrough connected to said container, a sealing seat in said passage, an axially movable plunger in said passage positioned perpendicularly to said frangible seal, said plunger being provided with a cutting edge for piercing said frangible seal and with a sealing plug positioned to close on said sealing seat, said plunger being adapted upon manual actuation to pierce the frangible disc and to allow passage of said fire-extinguishing agent through the housing passage into a discharge nozzle connected thereto and upon release of manual actuation the plunger is thereafter adapted to be automatically actuated away from said frangible seal and to position said sealing plug in sealing engagement with said sealing seat to affect a pressure tight seal, and locking means to immobile said plunger to prevent puncturing of the frangible seal or positioning of said sealing plug in sealing contact with said sealing seat unless said locking means is released.

2. A fire-extinguishing apparatus comprising a pres sure container for the fire-extinguishing agent, a frangible seal closing the mouth of said container, a housing having a passage therethrough connected to said container, a sealing seat in said passage, an axially movable plunger in said passage positioned perpendicularly to said frangible seal, said plunger being provided with a cutting edge for piercing said frangible seal and with a sealing plug positioned to close on said sealing seat, said plun er being adapted upon manual actuation to pierce the frangible disc and to allow passage of said fire-extinguishing agent through the housing passage into a discharge nozzle connected thereto and upon release of manual actuation the plunger is thereafter adapted to be automatically actuated away from said frangible seal and to position said sealing plug in sealing engagement with said sealing seat to affect a pressure tight seal, and a locking device to prevent puncturing of said frangible seal or seating of said sealing plug unless the locking device is released.

3. A fire-extinguishing apparatus comprising a pressure container for the fire-extinguishing agent, a frangible seal closing the mouth of said container, a housing having a passage therethrough connected to said container, a sealing seat in said passage, an axially movable plunger in said passage positioned perpendicularly to said frangi ble seal, said plunger being provided with a cutting edge for piercing said frangible seal and with a sealing plug positioned to close on said sealing seat, said plunger being adapted upon manual actuation to pierce the frangible disc and to allow passage of said fire-extinguishing agent through the housing passage into a discharge nozzle connected thereto and upon release of manual actuation the plunger is thereafter adapted to be automatically actuated away from said frangible seal and to position said sealing plug in sealing engagement with said sealing seat to affect a pressure tight seal, and a removable ring pin to prevent puncturing of said frangible seal and seating of said sealing plug and said sealing seat except when said ring pin is removed.

4. A fire-extinguishing apparatus comprising a pressure container for the fire-extinguishing agent, a frangible seal closing the mouth of said container, 21 housing having a passage therethrough connected to said container, a sealing seat in said passage, a spring urged lever for actuating an axially movable plunger in said passage, positioned perpendicularly to said frangible seal, said plunger being provided with a cutting edge for piercing said sealing seat, said plunger being adapted upon manual actuation of said actuating lever to pierce the frangible disc and to allow passage of said fire-extinguishing agent through the housing passage into a discharge nozzle connected thereto and upon manual release of said spring urged actuating means the plunger is thereafter adapted to be automatically actuated away from said frangible seal and to position said sealing plug in sealing engagement with said sealing seat to affect a pressure tight seal, and means to normally immobilize the plunger to prevent puncturing of frangible seal or positioning of said sealing plug in sealing contact with sealing seat unless said means is released.

5. A fire-extinguishing apparatus comprising a pressure container for the fire-extinguishing agent, a frangible seal closing the mouth of said container, a housing having a passage therethrough connected to said container, a sealing seat in said passage, a spring urged lever for actuating an axially movable plunger in said passage positioned perpendicularly to said frangible seal, said plunger being provided with a cutting edge for piercing said frangible seal and with a sealing plug positioned to close on said sealing seat, said plunger being adapted upon manual actuation of said actuating lever to pierce the frangible disc and to allow passage of said fire-extinguishing agent through the housing passage into a discharge nozzle connected thereto and upon manual release of said spring urged actuating means and plunger is thereafter adapted to be automatically actuated away from said frangible seal and to position said sealing plug in sealing engagement with said sealing seat to affect a pressure tight seal, and a removable ring pin passing through said actuating lever and said housing retaining said plunger to prevent puncturing of said frangible seal and seating of said sealing plug and said sealing seat except when said ring pin is removed.

References Cited in the file of this patent UNITED STATES PATENTS 

